A biomass gasifier

Abstract

The present invention relates to the technical field of biomass gasifiers, and particularly to a biomass gasifier. It includes a furnace body, inside which there is a furnace chamber. At the bottom of the furnace body, there is an electromagnetic induction heating device, which includes a heating section and a heat dissipation section. The heat dissipation section extends into the furnace chamber, and inside the heating section, there are a gas channel and a liquid channel; on the side wall of the furnace body, there is a heat exchange tube, and the heat exchange tube is connected to the liquid channel through a pipeline. The biomass gasifier provided by the present invention does not require the use of external fuel for heating, and does not sacrifice part of the biomass as fuel. It has a high biomass gasification conversion rate, and can use green electricity such as wind and light for heating, promoting the local consumption of new energy, saving the cost of external fuel. In addition, the gasifier also has a heat storage function. After the gasifier is shut down, it can still provide a heat source for external heating. At the same time, the gasifier is in a long-term hot standby state, which can shorten the start-up time of the gasifier.

Description

Technical Field

[0001] The present invention relates to the technical field of biomass gasifiers, and particularly to a biomass gasifier. Background Art

[0002] As a clean energy source, biomass is characterized by wide sources, large reserves, and dispersion. There are also multiple technical routes for the utilization of biomass as an energy source. Among them, biomass gasification is a main form of thermochemical process, and the gasifier is the core of the biomass gasification process. The current mainstream gasifier types include fixed-bed gasifiers and fluidized-bed gasifiers. The heating method of these two types of gasifiers generally uses fuel ignition, and then part of the biomass is burned to increase the temperature inside the furnace, so as to realize the pyrolysis and gasification of biomass. This heating method requires external fuel and sacrifices part of the organic matter of biomass as fuel to maintain the temperature inside the furnace, increasing the external fuel cost and reducing the effective gas conversion rate of biomass. In addition, the start-up time of these two types of gasifiers is relatively long, they do not have the function of storing and releasing heat, and the hot standby time is relatively short. Therefore, the present invention is proposed. Summary of the Invention

[0003] The purpose of the present invention is to provide a biomass gasifier, which does not require external fuel for heating, does not sacrifice part of the biomass as fuel, has a high biomass gasification conversion rate, and can use green electricity such as wind and light for heating, promoting the local consumption of new energy and saving the external fuel cost.

[0004] The present invention provides a biomass gasifier, including a furnace body. A hearth is arranged inside the furnace body. An electromagnetic induction heating device is arranged at the bottom of the furnace body. The electromagnetic induction heating device includes a heating section and a heat dissipation section. The heat dissipation section extends into the hearth. A gas passage and a liquid passage are arranged inside the heating section. A heat exchange tube is arranged on the side wall of the furnace body, and the heat exchange tube is communicated with the liquid passage through a pipeline.

[0005] Further, the heating section includes a first cylinder body. An alloy conductor is arranged inside the first cylinder body. An insulating and heat-preserving layer is arranged outside the first cylinder body. An induction coil is arranged outside the insulating and heat-preserving layer. The space between the first cylinder body and the alloy conductor is the gas passage.

[0006] Further, the shape of the alloy conductor is cylindrical, and a plurality of heat dissipation units are arranged on the outer peripheral wall of the alloy conductor along the vertical direction. Each heat dissipation unit includes four evenly distributed fins.

[0007] Further, the heat dissipation section includes a second cylinder body communicated with the first cylinder body. A plurality of air distribution openings are arranged on the side wall of the second cylinder body, and the opening direction of the air distribution openings is downward.

[0008] Further, a liquid channel is provided inside the alloy conductor, and a liquid pipeline is provided inside the heat dissipation section. Two ends of the liquid pipeline are respectively connected to the liquid channel and the heat exchange tube.

[0009] Further, two heat storage layers are provided on the side wall of the furnace body from inside to outside, and the heat exchange tube is provided between the two heat storage layers.

[0010] Further, the first cylinder body and the second cylinder body are integrally formed, and a sealing partition plate is provided at the upper part of the first cylinder body.

[0011] Further, the sealing partition plate is sleeved on the alloy conductor. The sealing partition plate includes two sector plates that can form an annular shape, and the sector plates are rotatably connected to the first cylinder body.

[0012] Further, a rotating shaft penetrates through the side wall of the sector plate, and two ends of the rotating shaft are rotatably connected to the first cylinder body. A driving mechanism is provided outside the first cylinder body, and an output end of the driving mechanism is fixedly connected to one end of the rotating shaft.

[0013] Further, a syngas outlet is provided at the top of the furnace body, a feed inlet is provided on the side wall of the furnace body, and a slag outlet is provided at the lower part of the furnace body; a grate is provided at the bottom of the furnace chamber; and a plurality of uniformly distributed support frames are provided at the bottom of the furnace body.

[0014] In summary, compared with the prior art, the present invention has the following advantages:

[0015] In the technical solution of the present invention, through the provided electromagnetic induction heating device, when in use, a heat-conducting liquid is first added to the liquid channel of the heating section, and the heat-conducting liquid is heated by using the electromagnetic induction principle and then enters the heat exchange tube, so that the temperature of the furnace chamber rises. The provided heat exchange tube enables the temperature of the furnace chamber to rise faster, can significantly increase the speed of the gasification reaction, and greatly shortens the start-up time of the gasifier from starting to full load. After the temperature of the furnace chamber rises, biomass is added, and at the same time, air or high-purity oxygen with a certain pressure is conveyed to the heating section. After being heated by using the electromagnetic induction principle, it enters the furnace chamber through the heat dissipation section to heat the biomass, generating crude syngas such as CO, CO 2 and H 2 etc. It does not need to use external fuel for ignition, nor does it need to sacrifice part of the biomass as fuel. It can heat two media at the same time, greatly improving the gasification conversion rate. It can locally consume new energy power generation such as wind and light, saving external fuel costs. In addition, the gasifier provided by the present invention also has a heat storage function. After the gasifier stops operating, it can still provide a heat source for external heating. At the same time, the gasifier is in a hot standby state for a long time, which can shorten the start-up time of the gasifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 Structural schematic diagram of the biomass gasifier in Embodiment 1 of the present invention;

[0018] Figure 2 Top view of the biomass gasifier in Embodiment 1 of the present invention;

[0019] Figure 3 Top view of the heating section in Embodiment 2 of the present invention.

[0020] Explanation of reference numerals: 1 - furnace body; 101 - furnace chamber; 102 - feed inlet; 103 - ash discharge outlet; 104 - grate; 105 - syngas outlet; 106 - manhole; 107 - heat storage layer; 108 - heat exchange tube; 2 - heating section; 201 - first cylinder; 202 - insulation layer; 203 - induction coil; 204 - alloy conductor; 205 - fin; 206 - mounting bracket; 207 - gas inlet; 208 - gas passage; 209 - liquid inlet; 210 - liquid passage; 3 - heat dissipation section; 301 - second cylinder; 302 - air distribution opening; 303 - exhaust port; 304 - liquid pipeline; 305 - fixing bracket; 4 - sector plate; 5 - driving mechanism; 6 - rotating shaft; 7 - support frame. Specific embodiments

[0021] The following will clearly and completely describe the technical solutions of the present invention in combination with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0022] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "a plurality of" means two or more unless specifically defined otherwise. In addition, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] Embodiment 1

[0025] A biomass gasifier, as Figure 1 and Figure 2 shown, includes a furnace body 1. Inside the furnace body 1, there is a hearth 101. At the top of the furnace body 1, there is a syngas outlet 105 communicating with the hearth 101. On the upper part of the side wall of the furnace body 1, two feed inlets 102 are symmetrically arranged; at the bottom of the hearth 101, there is a grate 104. The grate 104 adopts a conventional grate made of high-temperature resistant materials in the art. The gap of the grate is adjusted according to the size of the biomass material with the basic requirement of not dropping raw materials. At the lower part of the furnace body 1, there are two ash discharge outlets 103, and a manhole 106 is arranged at the lower part of the side wall of the furnace body 1.

[0026] An electromagnetic induction heating device is arranged at the bottom of the furnace body 1. The electromagnetic induction heating device includes a heating section 2 and a heat dissipation section 3. The heating section 2 is located at the bottom of the furnace body 1, and the heat dissipation section 3 passes through the bottom wall of the furnace body 1 and extends into the hearth 101. The heating section 2 includes a first cylinder 201. The first cylinder 201 is made of high-temperature resistant stainless steel. An insulating and heat-preserving layer 202 is wrapped outside the first cylinder 201. An induction coil 203 is wound outside the insulating and heat-preserving layer 202. The insulating and heat-preserving layer 202 adopts materials such as polyurethane and ceramics in the prior art.

[0027] The first cylinder 201 is provided with a cylindrical alloy conductor 204 inside, and a plurality of mounting brackets 206 for fixing the alloy conductor 204 are welded on the inner wall of the first cylinder 201. A plurality of heat dissipation units are provided on the outer peripheral wall of the alloy conductor 204 in the vertical direction. The heat dissipation unit includes four fins 205 evenly fixed on the same plane. The arrangement height of the heat dissipation unit is consistent with the winding height of the induction coil 203 and is located on the same horizontal plane. In this embodiment, the bottom of the first cylinder 201 is an open structure, and the annular space between the bottom of the first cylinder 201 and the bottom of the alloy conductor 204 is a gas inlet 207 for introducing air or oxygen at a certain pressure. The space between the first cylinder 201 and the alloy conductor 204 is a gas channel 208. The transported air or oxygen enters the gas channel 208, is heated by the electromagnetic induction principle, and then enters the furnace 101 through the heat dissipation section 3 to pyrolyze the biomass. When in use, the bottom of the first cylinder 201 is connected to the gas delivery device through a gas delivery pipeline.

[0028] The heat dissipation section 3 includes a second cylinder 301 connected to the first cylinder 201. A plurality of air outlets 302 are arranged on the outer peripheral wall of the second cylinder 301 in the vertical direction. The air outlets 302 are circular in shape and open downward to avoid blockage of the air outlets 302 when biomass is fed. A circular end cap is fixed on the top of the second cylinder 301. The end cap is located outside the furnace body 1. An exhaust port 303 is arranged at the center of the top of the end cap for hot air discharge. A regulating valve can be installed at the exhaust port 303 to adjust the exhaust port according to the synthesis gas (CO, H 2 and CO 2 The first cylinder 201 and the second cylinder 301 are integrally formed in the present invention. When installed, the second cylinder 301 is welded to the contact position of the bottom wall of the furnace body 1. The center lines of the first cylinder 201, the second cylinder 301 and the alloy conductor 204 are aligned with the center line of the furnace 101.

[0029] In this embodiment, the alloy conductor 204 is a hollow cylinder. A liquid channel 210 is provided at the axial center position inside it, and a liquid inlet 209 is provided at its bottom for connecting with a heat-conducting liquid pipeline and related supply equipment. The heat-conducting liquid can be water or heat-conducting oil. A liquid pipeline 304 is installed at the axial center position inside the heat dissipation section 3. A plurality of fixing brackets 305 are welded on the inner wall of the second cylinder body 301 for fixing the liquid pipeline 304. The bottom end of the liquid pipeline 304 is welded to the alloy conductor 204, and the liquid pipeline 304 communicates with the liquid channel 210. The top end of the liquid pipeline 304 communicates with the heat exchange tube 108 in the side wall of the furnace body 1. The side wall of the furnace body 1 is provided with two layers of heat storage layers 107 from the inside to the outside. A heat exchange tube 108 is arranged in the interlayer between the two layers of heat storage layers 107, and the end of the heat exchange tube 108 extends out of the furnace body 1. In this embodiment, the heat storage layer 107 adopts existing heat storage materials in the field. The heat exchange tube 108 can be arranged in a serpentine or U shape along the circumferential direction of the furnace body 1 in the interlayer of the heat storage layer 107. The arranged heat exchange tube 108 is mainly used for heat exchange with the heat storage material.

[0030] In the prior art, the cold start time of the gasifier is relatively long, and the furnace body is adiabatic and does not have the ability to supply heat externally. A large amount of heat cannot be utilized after the gasifier stops operating. Therefore, in this embodiment, a heat exchange tube 108 and a heat storage layer 107 are provided. During use, the bottom of the alloy conductor 204 is connected to the heat-conducting liquid pipeline, and water or heat-conducting oil is introduced into the liquid channel 210. The heated water or heat-conducting oil enters the heat exchange tube 108 through the liquid pipeline 304 to heat the heat storage material, so that the temperature rising speed of the furnace chamber 101 is accelerated, and the speed of the gasification reaction is significantly increased, greatly shortening the start-up time of the gasifier from startup to full load. During the gasification process, on the one hand, the heat exchange tube 108 can keep the temperature of the furnace wall stable, which is beneficial to keeping the biomass gasification in the high-efficiency temperature range all the time; on the other hand, a valve is installed at the end of the heat exchange tube 108 and connected to external equipment through an external pipeline, and the flowing liquid in the heat exchange tube 108 is used to supply heat externally.

[0031] After the gasifier stops operating, the heat stored in the heat storage layer 107 can still be used to supply heat externally through the heat exchange tube 108. According to the capacity of the heat storage material, the external heat supply time can be maintained for 4 to 8 hours, which can effectively balance the volatility of wind and photovoltaic power. Especially when the photovoltaic power generation is insufficient at night, the liquid in the heat exchange tube 108 can continue to be used as the heat source for external heat supply, improving the reliability of heat supply; at the same time, after shutdown, the heating section 2 can continue to intermittently heat the heat-conducting liquid in the heat exchange tube 108 to keep the furnace chamber 101 at a relatively high temperature, and the furnace body 1 is always in a hot standby state, shortening the time required for restart.

[0032] In this embodiment, the furnace body 1 is cylindrical, and three support frames 7 are welded to its bottom. The material of the support frames 7 is the same as that of the furnace body 1, and the three support frames 7 are evenly distributed along the edge of the bottom of the furnace body 1.

[0033] The method for using the biomass gasifier provided in this embodiment is as follows: first, the induction coil 203 is powered on to start the heating section 2, and water or heat-conducting oil is input into the liquid channel 210 of the alloy conductor 204. The heated water or heat-conducting oil enters the heat exchange tube 108, heats the heat storage layer 107, and raises the temperature of the furnace 101 to above 200°C (an infrared temperature detection device can be installed on the side wall of the furnace body 1 to detect the temperature inside the furnace); then, biomass raw materials are added to the furnace 101 through the feed port 102, and air or high-purity oxygen at a certain pressure is delivered through the gas inlet 207 (air or high-purity oxygen with a pressure of 2-5 bar can be delivered by a blower). The temperature of the air or oxygen rises in the heating section 2 through convection heat exchange with the alloy conductor 204 and after absorbing the radiation heat of the fins 205, the heat is transferred to the furnace 101 through the air outlet 302 of the heat dissipation section 3 to heat the biomass. The biomass is pyrolyzed and gasified at the corresponding temperature to finally generate CO and CO 2 and H 2 The crude synthesis gas is discharged from the furnace 101 through the synthesis gas outlet 105 and enters the downstream for further utilization; after the biomass is pyrolyzed and gasified, the inorganic part is discharged as ash through the ash outlet 103.

[0034] Example 2

[0035] A biomass gasifier. The technical solution of this embodiment is basically the same as that of embodiment 1, except that: (1) infrared temperature detection devices are respectively installed at the upper and middle parts of the first cylinder 201 to detect the heating temperature of the gas in the gas channel 208; (2) a sealing baffle is installed at the upper part of the first cylinder 201, and the sealing baffle is located above the induction coil 203. The sealing baffle is driven to open or close by a driving mechanism 5 installed outside the first cylinder 201.

[0036] Turn on the infrared temperature detection device. When the air or oxygen in the heating section 2 is heated to above 700°C, open the sealed partition to allow the heated air or oxygen to enter the heat dissipation section 3. Figure 3As shown in the figure, the sealing partition in this embodiment is annular and sleeved outside the alloy conductor 204. The sealing partition includes two sector plates 4. A rotating shaft 6 penetrates through the side wall of the sector plate 4, and both ends of the rotating shaft 6 are rotatably connected to the inner wall of the first cylinder 201. An installation bracket is fixed outside the first cylinder 201, and a driving mechanism 5 is placed on the installation bracket. The output end of the driving mechanism 5 is fixedly connected to one end of the rotating shaft 6. The driving mechanism 5 can adopt a motor in the prior art or other devices that can drive the rotating shaft 6 to rotate. When it is necessary to open the sealing partition, start the driving mechanism 5, and the driving mechanism 5 drives the rotating shaft 6 to rotate, thereby driving the sector plate 4 to flip, connecting the heating section 2 and the heat dissipation section 3, and enabling the heated air or oxygen to enter the heat dissipation section 3. When designing and installing the sector plate 4, the two sector plates 4 can only rotate upward to open and rotate downward to close. Two limit blocks can be installed on the alloy conductor 204, and the two limit blocks are respectively located at the bottom of the sector plate 4, so as to ensure that the sector plate 4 only opens upward and can be completely closed when closed; and high-temperature resistant sealing rings can be added at the gap where the sector plate 4 contacts the first cylinder 201 and at the contact edge of the two sector plates 4 to increase the sealing performance.

[0037] The usage method of the biomass gasifier provided in this embodiment is as follows: First, energize the induction coil 203 to start the heating section 2, input water or heat-conducting oil into the liquid channel 210 of the alloy conductor 204, and the heated water or heat-conducting oil enters the heat exchange tube 108 to heat the heat storage layer 107, so that the temperature of the furnace chamber 101 rises above 200 °C; then add biomass raw materials into the furnace chamber 101 through the feed port 102, and then convey air or high-purity oxygen with a certain pressure through the gas inlet 207. After the air or oxygen exchanges heat convectively with the alloy conductor 204 inside the heating section 2 and absorbs the radiant heat of the fins 205, the temperature rises above 700 °C. Open the sealing partition through the driving mechanism 5, and the heated air or oxygen enters the heat dissipation section 3. The heat is transferred into the furnace chamber 101 through the air distribution openings 302 of the heat dissipation section 3 to heat the biomass. The biomass undergoes pyrolysis gasification at the corresponding temperature and finally generates crude synthesis gas such as CO, CO 2 and H 2 etc., and is discharged from the furnace chamber 101 through the synthesis gas outlet 105 and enters the downstream for further utilization; after the biomass pyrolysis gasification, the inorganic part is discharged as ash through the ash outlet 103.

[0038] The biomass gasifier provided by the present invention, through the electromagnetic induction heating device provided, adopts the principle of electromagnetic induction to provide a new heat source for biomass pyrolysis gasification. When heating, no external fuel is required, nor is it necessary to sacrifice part of the biomass as fuel, which significantly improves the biomass gasification conversion rate. Moreover, the electromagnetic induction heating device can heat two media, liquid and gas, simultaneously, greatly improving the electro-thermal conversion efficiency. The heat exchange tubes provided on the side wall of the furnace body endow it with a heat storage function, which can not only absorb unstable power sources such as wind and light, but also keep the gasifier in a hot standby state, shorten the start-up time, and can also supply heat externally, having strong practicability.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A biomass gasifier, characterized in that: The invention comprises a furnace body (1), wherein a furnace chamber (101) is provided inside the furnace body (1), an electromagnetic induction heating device is provided at the bottom of the furnace body (1), the electromagnetic induction heating device comprises a heating section (2) and a heat dissipation section (3), the heat dissipation section (3) extends into the furnace chamber (101), and a gas channel (208) and a liquid channel (210) are provided inside the heating section (2); a heat exchange tube (108) is provided on a side wall of the furnace body (1), and the heat exchange tube (108) is connected to the liquid channel (210) through a pipeline; The heating section (2) comprises a first cylinder (201), an alloy conductor (204) is arranged inside the first cylinder (201), an insulating and heat-preserving layer (202) is arranged outside the first cylinder (201), and an induction coil (203) is arranged outside the insulating and heat-preserving layer (202); the space between the first cylinder (201) and the alloy conductor (204) is the gas channel (208); The heat dissipation section (3) comprises a second cylinder (301) connected to the first cylinder (201), a plurality of air distribution ports (302) are provided on the side wall of the second cylinder (301), and the opening direction of the air distribution ports (302) faces downward; The alloy conductor (204) is provided with the liquid channel (210) inside, the heat dissipation section (3) is provided with a liquid pipeline (304) inside, and the two ends of the liquid pipeline (304) are respectively connected to the liquid channel (210) and the heat exchange tube (108); The side wall of the furnace body (1) is provided with two layers of heat storage layers (107) from the inside to the outside, and the heat exchange tube (108) is provided between the two layers of heat storage layers (107).

2. The biomass gasifier according to claim 1, characterized in that: The alloy conductor (204) is cylindrical in shape, and a plurality of heat dissipation units are provided on the outer peripheral wall of the alloy conductor (204) in the vertical direction; each of the heat dissipation units comprises four evenly distributed fins (205).

3. The biomass gasifier according to claim 1, characterized in that: The first cylinder (201) and the second cylinder (301) are integrally formed, and a sealing partition is provided on the upper portion of the first cylinder (201).

4. The biomass gasifier according to claim 3, characterized in that: The sealing baffle is sleeved on the alloy conductor (204), and the sealing baffle comprises two sector plates (4) that can form a circular ring shape. The sector plates (4) are rotatably connected to the first cylinder (201).

5. The biomass gasifier according to claim 4, characterized in that: A rotating shaft (6) passes through the side wall of the fan-shaped plate (4), and both ends of the rotating shaft (6) are rotatably connected to the first cylinder (201); a driving mechanism (5) is provided outside the first cylinder (201), and an output end of the driving mechanism (5) is fixedly connected to one end of the rotating shaft (6).

6. The biomass gasifier according to claim 1, characterized in that: The top of the furnace body (1) is provided with a synthesis gas outlet (105), the side wall of the furnace body (1) is provided with a feed port (102), and the lower part of the furnace body (1) is provided with an ash outlet (103); the bottom of the furnace chamber (101) is provided with a grate (104); and the bottom of the furnace body (1) is provided with a plurality of evenly distributed support frames (7).

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